St. Leo the Great had this to say about human dignity (translated from the Italian):
“…Sinful humanity has found again innocence, the old man caught in sin has reacquired new life; the outcast has received adoption and the stranger has entered into possession of his inheritance.
“Awaken, O man, and reconsider the dignity of your nature! Remember that you have been created in the image of God; that if this resemblance was disfigured by Adam, it has been restored in Christ. Use the visible creatures in agreeable ways, like you might utilize the things of the earth, sea, heavens, air, the springs of water, of the rivers. Whatever you find of beauty and wonder in them, direct it to the praise and glory of the Creator.” (Disc. for Christmas, 7, 2.6)